Pendulum.



No. 783,747. PATENTED FEB. 28, 1905.

I F. 1. GETTY.

PENDULUM.

APPLICATION FILED SEPT. 26, 1902.

/ Z I Z UNITED STATES Patented February 28, 1905.

PATENT OFF CE.

FRED I. GETTY, OF CHICAGO, ILLINOIS, ASSIGNOR TO THE AMERICAN CLOCK COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF NEW JERSEY.

PENDULUNI.

SPECIFICATION forming part of Letters Patent No. 783,747, dated February 28, 1905.

Application filed September 26,1902. Serial No, 124,939.

To all whom, it nuty concern.-

Be it known that I, FRED I. GETTY, a resident of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Pend ulums, of which the following is a specification.

This invention relates to improvements in pendulums for clocks; and among the salient objects of the invention are to provide a construction which is so designed as to permit the same to be regulated to a given clock at the factory and then bodily removed and shipped without disturbing the adjustment; to provide a construction which permits the pendulum to automatically adjust itself to the vertical, regardless of variations from a plumb position of the clock, within reasonable limits; to provide a construction in which the supporting-block and the pendulum rod and bob necessarily retain a fixed relation to each other after adjustment, so that the lineal distance from the center of gravity of the pendulum-bob to the point of suspension remains the same, thereby insuring, in conjunction with the features hereinbefore mentioned, an exceedingly accurate and uniform-running clock; to provide a construction in which the adjustment to vary the length of the, pendulum may be most conveniently made and accurately determined, and, in general, to provide a simplified and improved construction of the character referred to.

To the above ends the invention consists in the matters hereinafter described, and more particularly pointed out in the appended claims, and the invention will be more readily understood from the following description by reference to the accompanying drawings, forming a part thereof, in which Figure 1 is a view, principally in elevation, but with the pendulum-bob shown in axial section, of a complete pendulum embodying my invention. Fig. 2 is a view of the pendulum rod and bob detached from the supportingblock and viewed in a direction at right angles to the position shown in Fig. 1. Fig. 3 is a top or plan View of the pendulum. Fig. i is a view showing one method of attaching the pendulum-block to the clock-movement frame.

Referring to the drawings, 1 designates as a whole the suspending-bloek, 2 the rod of the pendulum, and 3 the pendulum-bob connected therewith. The bob as shown herein is of the mercury-cup type, comprising a hollow receptacle 6L partially [illed with mercury 5 and closed at its upper end by means of a screwcap 6, with which latter the pendulum-rod is connected as usual.

The suspension-block 1 is of suitable hard and preferably resilient material -as, for example, brass-----and provided at its opposite sides or edges with axially-alined outwardlrextending trunnions I, which are adapted to rest in suitable hearings in the clock-frame, so as to permit the pendulun'i to rock freely forwardly and backwardly and to therefore assume an aecuratelyplumb position with reference to the vertical plane of said trunnions 7. Through the central portion of the suspension-block is formed an opening 8, and from said opening 8 a cut or slit 9 is extended downwardly through and eompletel y dividing the lower end of said suspension-block. The suspension-block is also provided with a vertical or axially-disposed bore 10, extending through the block and adapted to accommodate a round threaded extension 12, forming the extreme upper end of the pendulum-rod. The extension 12 of the pendulum rod is united with the main stem portion 13 by means of a thin ribbon-like strip of metal Min a familiar manner, the ends of the connected parts being slitted to receive said spring-strip ll. and the latter riveted therein, as shown clearly in Fig. 2. The upper end of the extension 12 is screw-threadml, and when the parts are assembled said extension occupies the here ll) of the suspension-block, while the connectingstrip 14: extends downwardly through the slit 9 of the block, as shown clearly in Fig. l. The divided lower end of the suspension-bleel; is so formed as to lightlyembrace or claspthe sides of the connecting-strip l-itwhen the latter is in position, so that the flexure of said strip during the oscillation of the pendulum occurs below the end of the suspension-block.

15 designates an adjusting nut threaded upon the upper end of the stem extension I2 and seated upon the upper end of the suspension-block, so as to raise or lower the stem relatively to the block by proper rotation.

Desirably an indicator-point 16 is lixed in the suspension-block and arranged to project adacent to the periphery of the nut 15, and the latter is provided with suitable graduationmarks, as 16, so that the amount of rotation of the nut may be determined.

1 11 order that the pend ulum-rod may be held against movement upwardly through the susshape of the clock makes it much more dillicult to perceive a lack of plumbness in this direction. The sound produced by the running of the clock obviously is not ptwceptibly different whether the clock be standing plumb with relation to its front and back sides or not.

\Yhile I have herein shown and described a is to be understood that the details of coni struction may be modilied without departing pension-block, especially during such time as i the pendulum is disconnected from the clock, a coiled expansion-spring 17 is arranged within the opening 8 and interposed between the upper end of the latter and a collar or annular shoulder 18, formed upon the extension 12, so as to exert a constant downward pressure.

The operation of the pendulum is the usual one, and the manner of adjusting the length of the pendulum to vary its time of beat is entirely obvious from the foregoing description. It is to be noted, however, that the idea of providing a suspension-block which becomes, in effect, a part of the pendulum itself, so that the pendulum may be detached as a whole after adjustment for shipment, is deemed a matter of much importance. It is found in practice that it is practically impossible to adjust a clock to run accurately and find this adjustment retained after the pendulum has been removed and the parts subjected to a shipment and the incident shaking and vibration where the suspending and adjusting mechanism is a part of the clock mechanism as distinguisl'ied from being a part of the pendulum itself. ilt has been attempted to avoid this difliculty by providing the adjustment at the lower end of the pendulum-stem and between the latter and the pendulum-bob; but such a construction has many disadvantages and is not practically the equivalent of the construction shown herein. It is thought, furthermore, that it is broadly new to provide a suspension-block wherewith the pendulum proper is adjustably connected and which pendulum-block is adapted for pivotal connection with the clock mechanism proper, so as to provide for pivotal movement in a plane at right angles to the normal oscillation of the pendulum. This is obviously a feature of great importance, since it is found in practice that a large proportion of the inaccuracy in time-keeping qualities of clocks of the pendulum type is due to inaccurate setting of the clock-case in plumb position, and while clocks are usually adjusted to an a mroximately accurate plumb position with reference to their sides because the tick or beat of the clock is audibly uneven unless the clock be approximately plumb in this direction. yet clocks are extremely liable to be.

out of plumb with reference to the front and back of the case, both because there is no way of nicely determining when this is the case (except by means of a level) and because the from the invention. and i do not, therefore, limit myself to these details except to the extent that they are made the subject of specific claims.

I claim as my invention 1. In a pendulum, a pendulum-rod provided at its lower end with a bob, a suspension-block mounted axially and adjustably upon the upper end of said rod, an :uljusting-nut threaded upon the upper end of said rod and resting upon said suspension-block, a spring mounted upon said rod within said block and tending to increase the frictional contact between said block and said adjusting-nut to prevent the latter from turning, and means for pi votally connecting said suspension-block to the frame of a clock-movement.

In a pendulum, a pend ulum-rod provided with a flexible portion near its upper end and its lower end with a bob, a suspension-l lock mounted adjustably upon the upper end of said rod adjacent said flexible portion, said block being provided with means for pivotally attaching it to a clock-movement frame to oscillate in a plane at right angles to the plane of normal oscillation of said pendulum, an adjusting-nut threaded upon the upper end of said rod and resting upon said suspensionblock, and means for :frictionally locking said nut against turning, for the purpose d cscribed.

3. A pendulum, comprising in combination a rod having a flexible portion near its upper end and supporting a bob at its lower end, a suspension-block mounted axially and adjustably upon the upper end of said rod adjacent said flexible portion, an adj usting-rmt tl'ireaded upon the upper end of said rod and resting upon said suspension-block, means for holding said adjusting-m1t in adjusted position upon said rod, and means upon said suspensionblock for pivotally and detachably attaching it to a clock-movement frame to oscillate in a plane at right angles to the plane of normal oscillation of the pendulum-rod, for the purpose described.

L. In a pendulum, the combination with a pendulum rod and bob, said pemlulum-rml being provided with a flexible portion near its upper end, of a suspension-block axially and adjustably mounted upon the upper end of said rod adjacent said flexible portion, an adjusting-mt threaded upon the end of said rod and resting upon said block, a spring tending to increase the frictional contact between said suspension-block and said adjusting-nut to prevent the latter from turning, and means for pivotally attaching said suspension-block to a clock-movement frame to oscillate in a plane at right angles to the plane of normal oscillation of said pendulum-rod.

Apendulum, comprising in combination, a pendulum-rod provided near its upper end with a flexible portion and at its lower end with a bob, an integral suspension block mounted axially and adjustably upon the upper end thereof adjacent said flexible portion, said block being provided at its sides with supportingtrunnions whereby to be pivotally and detachably mounted upon the frame of a clock-movement to oscillate in a plane at right angles to the plane of normal oscillation of said pendulum-rod, an adj Listingnut threaded upon the upper end of said rod and resting upon said suspension-block, and a coiled expansion-spring mounted upon said rod within said block and tending to increase the frictional contact between said block and said adjusting-nut to prevent the latter from turning, substantially as and for the purpose described.

6. In a pendulum, the combination with a pendulum-rod provided with a flexible portion near its upper end and a bob at its lower end, of a suspension-block mounted axially and adjustably upon the upper end of said rod, a thumb-nut threaded upon said rod and resting upon said block. said thumb-nut being provided with gradnation-marks, an indicatorpoint upon said suspension-block adjacent said thumb-nut, a spring tending to increase the frictional contact between said block and said nut to prevent the latter from turning, and means for pivotally attaching said suspension-block to the frame of a clock-movement to oscillate in a plane at right angles to the plane of normal oscillation of said pendulum-rod, substantially as described.

'7. In a pendulum, a pendulum-rod provided at its lower end with a bob and at its upper end with an extension, a suspension-block adjustably mounted upon said extension, an adjusting-nut threaded upon said extension and resting upon said suspension-block, a coiled spring around said extension within said block and tending to draw said extension through said block and increase the friction between said block and said adjusting-nut to prevent the latter from turning, and oppositely-disposed trunnions mounted upon the FRED I. GETTY.

\Vitncsses:

ALBERT H. GRAvEs, FREDERICK C. GOODWIN. 

